Traditionally, ophthalmic lenses such as spectacles for correction of human vision have required curved optical surfaces of dielectric materials such as glass or plastic. The same is true for devices that combine vision correction with other functions; such devices include prescription sunglasses, prescription swimming goggles, prescription skiing googles, and goggles that combine both protection from ballistic projectiles and vision correction. All such ophthalmic devices depend on the refraction of light by dielectric media. Typically, fabrication of the lenses of such devices is time-consuming and expensive since it requires grinding, polishing, and/or molding of the glass or plastic optics in order to create curved surfaces that refract the light as needed. Thus, there is a need for lenses that could be obtained in the form of thin film structurally continuous coatings on a variety of substrates, and for methods of creating ophthalmic lens functionality quickly and at low cost.
Related art for intraocular lenses, that is, lenses that are surgically implanted into a patient's eye to replace a defective or missing natural eye lens, includes intraocular lenses that employ diffractive coatings that provide multiple focal regions, providing simultaneous high-quality vision for both near and far objects. The present invention provides an alternative method for providing multiple focal ranges, with methods that are inherently less difficult to fabricate and lower cost.
Thus, the need exists for solutions to the above problems with the prior art.